1. Field of the Invention
This invention relates to a manual transmission having a reverse, and more particularly to a manual transmission having a reverse in which shifting is effected by way of a synchronizer.
2. Description of the Prior Art
As is well known, gear shifting in the manual transmission is effected by selectively bringing one of the gear trains into driving engagement. Manual transmissions are divided into several types, such as the selective sliding type, permanent mesh type, synchromesh type and the like according to the manner of selectively bringing one of the gear trains into driving engagement. For a vehicle, the synchromesh type transmission is generally employed so that shifting can be easily effected while the vehicle is in motion. However, if the transmission is arranged so that the gear can be easily shifted into reverse, for example, there is a fear that the reverse gear may be selected by mistake when the intended gear selection was fourth gear from fifth gear when the direction of motion of the shift lever in fifth gear is in line with that for selecting reverse gear as shown in FIG. 5. Accordingly, a selective sliding type transmission mechanism or the like has been employed for reverse so that the gears cannot be shifted into reverse too easily.
On the other hand, in the conventional manual transmission in which the selective sliding type transmission mechanism is employed for reverse, there has been a problem that when there is a rapid shift into reverse gear from a forward gear, the shift into reverse does not proceed smoothly and is apt to be accompanied by noise owing to the rotation of the idler gear and shaft which continue to rotate for a while under the force of inertia. Thus, it has been proposed to employ the synchromesh type transmission mechanism also for reverse. See Japanese Unexamined Pat. Pub. No. 60(1985)-44640, for instance.